Diseases of the Horse's Foot - BestLightNovel.com
You’re reading novel Diseases of the Horse's Foot Part 13 online at BestLightNovel.com. Please use the follow button to get notification about the latest chapter next time when you visit BestLightNovel.com. Use F11 button to read novel in full-screen(PC only). Drop by anytime you want to read free – fast – latest novel. It’s great if you could leave a comment, share your opinion about the new chapters, new novel with others on the internet. We’ll do our best to bring you the finest, latest novel everyday. Enjoy
The modified Charlier, or Charlier tip, perhaps the better of the two for the purpose we are describing, is really a shortened Charlier, and bears the same relation to the Charlier proper as the tip does to the ordinary shoe. It is let into the solar surface of the foot in exactly the same manner as its larger fellow, but it does not extend backwards beyond the commencement of the quarters. By its use greater opportunity for expansion is given to the heels than is done by the Charlier with heels of full length.
[Ill.u.s.tration: FIG. 67.--FOOT PREPARED FOR THE CHARLIER SHOE.]
We do not here intend to deal at any length with the arguments for and against the Charlier as regards its adoption for general use. These will be found fully set out in any good work on shoeing.
The point that it is correct in theory it would be idle to attempt to evade; but that it is generally practicable, or that it offers any very p.r.o.nounced advantages, as compared with the disadvantages urged against it, over the shoes in ordinary use, the limited favour it has drawn to itself, since its introduction in 1865, seems sufficiently to deny.
_(c) By the Use of a Bar Shoe_.--Where the frog is not excessively wasted benefit will be derived from the use of a bar shoe.
[Ill.u.s.tration: FIG. 68.--BAR SHOE.]
The transverse portion at the back, termed the 'bar,' and which gives the shoe its name, is instrumental in bringing about from below that counter-pressure on the frog that we now know to be so necessary a factor in remedying contraction. When the frog, by wasting or disease, is so deficient as to be unable to reach the 'bar,' this shoe must be supplemented by a leather or rubber sole.
In the event of corn or sand-crack existing with the contraction, the shoe known as a 'three-quarter bar' is preferable (see Fig. 103). The break here made in the contour of the shoe allows of dressing the corn, and, in the case of sand-crack, removes the bearing from that portion of the wall.
_(d) By the Use of a Bar Pad and a Heelless or 'Half' Shoe_.--The bar pad consists of a shape of rubber composition firmly fixed to a leather foundation, which shape of rubber takes the place of the 'bar' of the bar shoe.
[Ill.u.s.tration: FIG. 69.--RUBBER BAR PAD ON LEATHER.]
[Ill.u.s.tration: FIG. 70.--THE BAR, PAD APPLIED WITH A HALF-SHOE.]
For habitual use in such cases as prove obstinate to treatment, or where a complete cure was never from the commencement expected, the bar pad is undoubtedly one of the most useful inventions to our hand. The animal's 'going' is improved, the tender frog is protected from injury by loose stones, and greater comfort given to both the horse and the driver.
[Ill.u.s.tration: FIG. 71.--FROG PAD.]
[Ill.u.s.tration: FIG. 72.--FROG PAD APPLIED.]
_(e) By the Use of a Frog Pad and a Shoe of Ordinary Shape_.--The shape of rubber on this pad is designed to cover the frog only. Its shape and mode of application is sufficiently shown in the accompanying ill.u.s.trations.
_(f) By turning out to Gra.s.s_.--Where the expense of keep is no object, a return of contracted feet to the normal may be brought about by removing the shoes and turning the animal out to pasture, thus giving the feet the advantages to be derived from a more or less continuous operation of the normal movements of expansion and contraction. In this case the treatment must extend from three to four, or possibly six months.
2. _By the Use of Some Form of Expansion Shoe_.
[Ill.u.s.tration: FIG. 73.--SMITH'S EXPANSION SHOE SEEN FROM ITS GROUND SURFACE AND FROM THE SIDE. _a_, The screw, with a fine-cut thread; _b_, nut which travels along it; _c_, a hollow thimble into which the screw pa.s.ses at one end, the other being cut out V-shaped to catch into a slot (_d_) on the shoe; _e, e_, the grip[A] for the bars, the length and direction of which depend upon the shape of the foot; _f, f_, the counter-sunk rivets forming the hinge (_f_'); _g_, the counter-sunk rivet of the expanding piece.]
[Footnote A: The inventor of this shoe uses the word 'grip' to denote what, in describing other expansion shoes, we term the 'clip' (H.C.R.).]
_(a) Smith's_.--For many years past continental writers have been practising this method. So far as we know, however, Lieutenant-Colonel Fred Smith was the first English veterinarian to use a shoe of his own devising, and to report on its effects. This shoe we will, therefore, give first mention.
The above figure, with its accompanying letterpress, sufficiently explains the nature of the shoe. In fitting the shoe, care must be taken to have the hinges (_f, f_) far enough back, or the shoe will have a tendency to spring at the heels, and the grips _(e, e)_, which catch on the bars, will have a difficulty in biting. This trouble will be avoided by having the hinges about 1-1/2 to 2 inches from the heels.
After the shoe has been firmly nailed to the foot, the travelling nut _b_ is driven forward on the screw _a_ so as to cause the grips to just catch on the inside of the bars of the foot. According to the inventor, the amount of pressure to be exerted must be learned by experience, and he says:
'I screw up very gradually until I see the cleft of the frog just beginning to open. I now trot the horse up, and if he goes sound it is certain that the pressure I have exercised will not give rise to trouble. The animal is sent to work to a.s.sist in the expansion of the foot. On examining the shoe next day, the grip is found to be quite loose, the foot has enlarged, and the nut is turned once more until the grip on the bars is tightened, the horse being again trotted to ascertain that no injurious pressure is exerted.
'Every day or two I repeat this process, making measurements in all cases before widening the heels. The increase in width of the foot which results is astonis.h.i.+ng, 1/4 to 3/8 inch during the first week may be safely predicted, and in a month to six weeks it is impossible to recognise in the large healthy frog and wide heels, the shrivelled-up organ of a short time before.'[A]
[Footnote A: _Journal of Comparative Pathology and Therapeutics_, vol. v., p. 98.]
It is pointed out by the writer of the above (and his observations, doubtless, apply to the use of all other expansion shoes in which the bars are gripped and forcibly expanded) that the whole secret of success lies in avoiding injurious pressure by exerting too great an expansion at one operation. After each manipulation of the expanding apparatus the horse should trot sound and the frog remain cool. Should the foot become hot, and lameness supervene, then tension should at once be relaxed.
_Recorded Cases of the Use of the Shoe_.--The inventor of the shoe relates two cases of contracted foot treated by these means in which the heels of one, after thirty-nine days' treatment, had increased in width to the extent of 1 inch, and the heels of the other, after twenty-four days', had enlarged 5/8 inch. Of the first case he gives the drawings in Fig. 74.
A represents the foot before treatment; B the same foot after nine days'
treatment, when the heels had widened 3/4 inch; and C the same foot at the end of the thirty-nine days' treatment, at which date the frog was an excellent-looking one, and the foot had increased an inch in width.[A]
[Footnote A: _Journal of Comparative Pathology and Therapeutics_, vol. v., p. 100]
[Ill.u.s.tration: FIG. 74.--THE CHANGES IN FORM OF A CONTRACTED FOOT TREATED WITH SMITH'S EXPANSION SHOE]
In 1893, at a meeting of the Midland Counties Veterinary Medical a.s.sociation, the late Mr. Olver said he had applied this shoe to a valuable hunter that had gone so lame that he could scarcely put his foot to the ground. After a fortnight's application, and by the a.s.sistance of the double screw in the shoe, the heel was forced out. Then the horse was put to work with the shoe on, and he had hunted the whole of the last season in a perfectly sound condition.[A]
[Footnote A: _Veterinary Record_, vol. vi., p. 143]
F.D. McLaren, M.R.C.V.S., writes:[A] 'I resolved to try one of Captain Smith's shoes in a case where the hoof was badly contracted, and where the frog had entirely disappeared, there being also slight lameness. The roof rapidly expanded, and every other day the nut was moved on a bit to keep the cross-piece tight. I then had the cross-piece bent downwards a little _to prevent the nut pressing on the rapidly-growing frog_.[B] After another fortnight or so, I had a shoe made with clips resting against the inside of the bars,[C] and the next time he was shod these were also dispensed with.
It is now a year ago since the animal recovered his frog, and he still has the largest frog in the stable, and the hoof shows no sign of contraction.'
[Footnote A: _Ibid_., vol. vi., p. 183]
[Footnote B: The italics are mine (H.C.R.).]
[Footnote C: The expanding shoe itself was here evidently dispensed with, and an ordinary shoe with bar-clips used in its stead (H.C.R.).]
_(b) De Fay's_.--Among other shoes of the expansion cla.s.s may be mentioned that of De Fay. Like the preceding, it is a shoe with a flat bearing surface, and provided with bar-clips. It is, however, _un_ hinged. The requisite degree of periodic expansion is in this case arrived at by a forcible widening of the heels of the shoe, accomplished by bending the substance of which it is made, and for this purpose the instrument ill.u.s.trated in Fig. 75 is employed.
The foot is first properly trimmed by levelling the heels and thinning the sole on each side of the frog. The shoe is then fixed by nails in the ordinary manner, taking care that the last nails come not too far back, and that the clips rest evenly and firmly on the inside of the bars.
The dilator, hoof-spreader, or vice, as it is variously called, is then applied, its two jaws (_a_ and _b_) fitting against the inner edge of the shoe at the heels. Careful note is taken of the width of the hoof as measured on the graduated scale (_e_, _e_), and the double screw (_g_, _h_) revolved by means of the wrench (k), until the opening of the jaws thus obtained registers an expansion of 1/12 to 1/8 inch.
The dilatation is repeated at intervals of from eight to ten days, until, at the expiration of a month or six weeks, the amount of total expansion of the heels registers nearly an inch. That the method requires the greatest care may be gathered from the reports of continental writers. They state that frequently the pain and consequent lameness keep the patient confined to the stable for several days.
Numerous and but slightly differing forms of the dilator are on the market.
As in principle they are all essentially the same, and are to be found ill.u.s.trated in any reliable instrument catalogue, they need no description here.
[Ill.u.s.tration: FIG. 75.--DE FAY'S VICE.]
_(c) Hartmann's_.--A further useful expansion shoe is that of Hartmann's (Fig. 76), in that it may be adapted for either unilateral or bilateral contraction. This shoe is also provided with bar-clips, and forcibly expanded at the heels by means of a dilator. The expansion is governed by saw-cuts through the inner margin of the shoe directed towards its outer margin, and running only partially through the inner half of the web (see Fig. 76).
According as the contraction is confined to the inner or outer heel, the saw-cuts, one or two in number, are placed to the inner or outer side of the toe-clip. When the contraction is bilateral, the saw-cuts, one or more in number, are placed on each side of the toe-clip.
_(d) Broue's_.--This is one of the forms of so-called 'slipper' shoes (see Fig. 77). We have already indicated that the shape of the bearing surface of the ordinary shoe--by its 'seating' or sloping from outside to inside--is sometimes a cause of contraction. In the 'slipper' of Broue this bearing is reversed, and the slope is from inside to outside. In the original form of this shoe the slope to the outside was continued completely round the shoe. Experience taught that the strain this enforced upon the junction of the wall with the sole was injurious, and that the 'reversed seating,' if we may so term it, was best confined to the hinder portions of the shoe's branches.
[Ill.u.s.tration: FIG. 76. This figure ill.u.s.trates the principle of the Hartmann expanding shoe. _a, a_, The clips to catch the inside of the bars; _b, c_, saw-cuts.]
The amount of slope should not be excessive. If it is, too rapid and too forcible an expansion takes place, and pain and severe lameness results.
Dollar gives the requisite degree of incline by saying that the outer margin of the bearing surface of the shoe should be from 1/12 to 1/8 inch lower than the inner.
In the case of the Broue slipper, it is the animal's own weight that brings about the widening of the heels, the slope or outward incline of the slipper simply causing the inferior edge of the wall at the heels to spread itself outwards instead of sliding inwards on the bearing surface of the shoe.
[Ill.u.s.tration: FIG. 77.--THE SLIPPER SHOE OF BROUe.]